In a wireless communication system, portions of transmission data may sometimes be lost at once due to fading. If consecutive data bits are lost at once, this error cannot be recovered from even when a very excellent error correction code is used.
In a wireless communication system, a transmitting side transmits encoded transmission data streams after changing the order of the transmission data streams according to a specific pattern using a channel interleaving method rather than transmitting the data streams in an order in which the data streams are input. That is, a burst error that frequently occurs on a radio link may be changed to a random error using channel interleaving.
When error bits are sparsely present among sequences of the encoded transmission data, the error bits may be corrected using an error correction code such as a convolutional code, a turbo code, or a Low Density Parity Check (LDPC) code.
Basically, turbo coding, which is a channel coding technology, is a scheme which connects convolutional codes through parallel concatenation. The Convolutional Turbo Code (CTC) is one of the channel codes used in mobile Internet services.
As is well known, a next-generation mobile communication system requires reliable transmission of multimedia data at a high speed and requires robust channel coding and an efficient modulation scheme in order to increase reliability of high-speed data transmission. Accordingly, options enabling high-speed data transmission have been suggested and introduced in many countries in accordance with specifications of the options. As a result, various coding schemes such as convolutional coding or turbo coding have been suggested. Such channel coding schemes exhibit better performance depending on an interleaver size or a data block size corresponding to the interleaver size. Thus, intensive studies have been carried out on an interleaver that greatly affects turbo code performance.